BackgroundCore stability exercises (CSE) have been shown to be effective in improving trunk function in several neurological diseases, but the evidence is scarce on Hereditary Ataxias (HA).ObjectiveTo evaluate the effectiveness of a 5‐week home‐based CSE program in terms of ataxia severity, trunk function, balance confidence, gait speed, lower limb motor function, quality of life, health status and falls rate in HA individuals at short‐ and long‐term.MethodsThis is an assessor‐blind randomized controlled clinical trial parallel group 1:1. The individuals were divided in experimental group (EG) performed standard care in addition to CSE, and control group (CG) performed standard care alone. The CSE home‐program was conducted 1‐h/day, 5‐day/week for 5‐week. The assessment was performed at baseline, endpoint (5‐week), and follow‐up (10‐week). The primary outcomes were ataxia severity assessed by the Scale for the Assessment and Rating of Ataxia and trunk function assessed by Spanish‐version of Trunk Impairment Scale 2.0. The secondary outcomes were balance confidence assessed by Activities‐specific Balance Confidence (ABC), gait speed by 4‐meter walk test (4‐MWT), the lower limb motor function by 30‐s sit‐to‐stand, quality of life by EuroQol 5‐dimension 5‐level (EQ‐5D‐5L), health‐status by EQ‐5D and falls rate.ResultsTwenty‐three HA individuals were recruited (51.8 ± 11.10 years). Statistically significant group‐time interaction was shown in ABC (F:5.539; P = 0.007), EQ‐5D‐5L Total (F:4.836; P = 0.013), EQ 5D (F:7.207; P = 0.006).ConclusionsNo statistical differences between groups for ataxia severity and trunk function were observed. However, were differences for balance confidence, gait speed, quality of life, and falls rate in HA individuals.